Determination of landslide susceptibility in linear infrastructure. Case: aqueduct network in Palacé, Popayan (Colombia)

Abstract

This research aimed to predict the occurrence of mass movements in the aqueduct network of Palacé, in the municipality of Popayan (Colombia). We evaluated the quality of SRTM and ASTER digital terrain models by comparing them with contour lines using a map scale of 1: 25000. The landscape parameters derived from the SRTM-DEM were analyzed with a multivariate procedure using algorithms implemented in free software, along with thematic information of the study area (coverage, distance to faults, rivers and precipitation). We selected non-redundant variables with the non-parametric ACP technique, and obtained a susceptibility prediction model using logistic regression, with two types of variables: dependent (landslides inventory from field observation) and independent (slope, slope length factor, topographic wetness index, flow path length, soil units and rate of convergence) resulting in a susceptibility map, reclassified into categories according to the values of probability. The prediction model could not be quantitatively assessed because of the absence of studies with a semi-detailed scale, but the estimation of the mean square error of elevation, from which the terrain parameters were derived, the level of detail and the performance of the classifier with ROC curve, yielded a zoning consistent with the findings of the field visits.

Landslide Susceptibility Analysis on the Vicinity of Bogotá-Villavicencio Road (Eastern Cordillera of the Colombian Andes)

“…Finally, Pradhan et al [51] and Ramos-Cañon et al [59] catalogued rock falls, avalanches, rotational and translational landslides, earth-mud flows and debris flows. In other parts of the country, such as the Western and Central Cordilleras, shallow slides, falls, debris flows and mud-flows have been identified [5,[24][25][26][27]29,45,50,55]; in the southern Colombian Massif, specifically in Mocoa, debris flows, debris avalanches and shallow slides have been found [8,21,30,31].…”

“…Regarding factor analysis, the number of factors to be used in the models can be very high, especially in machine learning models [33], where it is common not to perform factor selection and allow the algorithms to fit the models. In this work, 12 variables have been used, which more or less coincide with those used in previous studies on susceptibility modelling, both globally [35,36,38,[40][41][42]90,97,103,104,106,107] and in Colombian Andes [31,[44][45][46][47][48][49][50][51][52][53]. Among them, the ones derived from the DEM stand out, which are related to the spatial distribution of important parameters such as slope, morphology, soil moisture or flow direction [51,117,118]; those related to geology and the geomechanical characteristics of materials [119] or those related to land use and land cover [81].…”

“…Different studies have been conducted in the Colombian Andes, using all types of methods from index-based methods such as frequency ratio or weight of evidence [44][45][46][47][48]; statistical methods such as logistic regression [31,46,[48][49][50][51]; machine learning methods such as random forest [46], graded boosted regression trees, GBRT [46] or multivariate adaptive regression [31] and simple [46,52] or convolutional neural networks [53]. The methods have been applied to different areas such as Capitanejo in the NE of the country [52], Medellín and the department of Antioquia to the NW [47][48][49], Caldas [44], Cauca [45,50], Boyacá [52], Bogotá and Cundinamarca [46,51] and Mocoa in the south [31]. Most of these studies, not only in Colombia but also throughout the world, do not take into account the landslide typology, which produces less precision and noise in the models.…”

“…Finally, it should be mentioned that those methods for determining rainfall thresholds and, where appropriate, establishing early warning systems, exist throughout the whole country [54] or in different departments such as Bolívar, Antioquia and Caldas to the northwest [50,[55][56][57][58] or in Bogotá [59]. Regarding precipitation, the influence of deep convective systems [60] and the impact of climate change on the generation of landslides and other risks [61] have also been evaluated in these previous works.…”

Diseño e implementación de un sistema de monitoreo de parámetros de calidad de agua en cultivo de tilapia en una granja piscícola del departamento del Cauca

“…Se diseñó un dispositivo electrónico para monitorear temperatura, pH, amoniaco y oxígeno disuelto en el agua para los estanques de tierra ubicados en la granja piscícola "Mamá Lombriz" ubicada en 2°30'55.8"N 76°34'08.7"O, con una altitud de 1.740 msnm, en el municipio de Popayán en el departamento del Cauca, como se muestra en la Figura 1. De acuerdo al registro climático, la zona tiene oscilaciones en el rango de 13°C a 27°C dependiendo de la temporada, los fenómenos climáticos y la hora del día; se reporta una temperatura promedio de 18°C (Correa-Muñoz & Higidio-Castro, 2017). Los principales parámetros de monitoreo se definieron en colaboración con la comunidad piscicultora, quienes identificaron algunas de las características importantes en el agua para garantizar un ambiente de crecimiento propicio y baja mortalidad para los alevinos.…”